This invention relates to methods for removal of gases from enclosed spaces and to vacuumized articles prepared thereby.
In the production of various thermal insulating articles such as vacuum bottles, it is well known to evacuate enclosed spaces provided in such articles and subsequently to seal the enclosed spaces from the atmosphere. A wide variety of methods for accomplishing the vacuumization of such articles are known, for example, as described in U.S. Pat. Nos. 3,167,159, 3,828,960 and 3,114,469.
Unfortunately, most conventional vacuumization methods require prolonged pumping to evacuate gases or prolonged heating periods to activate the gas absorbing materials (getters) in order to achieve the desired high level of evacuation, i.e., below 10.sup.-.sup.1 Torr (mm Hg) for vacuum bottles filled with getters and below 10.sup.-.sup.4 Torr for vacuum bottles containing no getter.
Therefore it would be highly desirable to provide an efficient method for evacuating enclosed spaces without the use of mechanical means to draw vacuum or prolonged heating periods to activate conventionally employed getters.